Why might an oxygen flow meter reading higher than the actual flow indicate an issue while using heliox?

The correct answer highlights an important property of helium when compared to oxygen. Helium is significantly less dense than oxygen, which directly affects how flowmeters read gas flows. Many oxygen flowmeters are designed to measure the flow of gases based on their density and viscosity characteristics, which are calibrated specifically for oxygen.

When heliox (a mixture of helium and oxygen) is used, the reduced density of helium can lead to inaccurate readings on flowmeters designed for oxygen. Since the flowmeter may interpret the lighter, less dense heliox as having a higher flow than it actually does, this results in a reading that misrepresents the true flow rate of the gas being delivered.

Understanding this property is crucial for those administering therapies involving heliox, as it informs proper dosages and delivery for effective patient care. Adjustments in treatment protocols may be necessary to ensure that the desired therapeutic effects are achieved safely and accurately when using heliox.